Actually, although the calculations were off by 8-fold in terms of mass, the final [DNA] was 3 higher than the upper-bounds of the recommended amount in terms of mass (1-10μg/mL), but at the low end of the recommended amount in terms of moles (0.1-1μM). Fortuitously, I think this was the right amount of DNA to use in this ligation.

Kathryn Muratore 10:08, 28 July 2011 (EDT): I did not subtract the background previously. This is now corrected.